Abstract
A. Lavoisier, C. L. Berthollet y H. Davy enjoy a significant place in the history of chemical theory. A closer examination of all their contributions reveals that they played as well an important role in fields properly related to practical issues. This wide range of occupations was something assumed by a great number of chemists of the period considered in this study, the second half of the XVIIIth Century and the beginning of the XIXth Century. Thus the paper will focus on offering details of the areas that drew the attention of relevant chemists of the period mentioned and on the ideas that legitimize their labours.